FCGR2B and chronic myelogenous leukemia, BCR-ABL1 positive: CML cells from transgenic mice (Fig. 1d) and human CML cell lines K562 and KCL-22 (Fig. 1e) were treated with IM and this showed persisting FcγRIIb expression; TKI treatment even enhanced FcγRIIb mRNA expression in the latter cell line.